The present invention relates to guides for knives used in the cutting of paperboard and similar materials, and more specifically to guides for selectively making either a circular or a straight cut with a beveled edge of desired angle relative to the surface of the material.
In the mounting and framing of pictures or other articles, it is common practice to provide a border of one or more layers of relatively thick paperboard, or a similar material, often having a colored surface and an interior which is white or of another shade differing from the surface color. The size and shape of the cut-out area depends upon the nature of the object to be bordered thereby, but in the majority of cases, the edge(s) of both the outer periphery and the cut-out portion are either straight, forming, e.g., a square or rectangular area, or circle.
A cutting tool commonly used in preparing paperboard matting or framing materials is known as a mat knife, comprising a hollow handle of two pieces, releasably attached by one or more screws and holding a separate, metal blade. While it is normally a simple matter to cut straight edges by drawing the knife blade along a linear member placed on the surface of the paperboard, circular cuts present a different problem. Templates of circular or other form are commonly used, but of course are fixed in size which limits the size and shape of the cut to the templates available at a given time.
It is also usually desired that the cut-out area, and sometimes the outer periphery, of the paperboard be cut with a beveled edge. That is, decorative effects may be achieved by exposing, by way of a tapered or beveled edge, the interior of the paperboard material which is commonly of a color contrasting with or complementing the surface color. It is often difficult to control the angle of the bevel, and thus to provide a neat and uniform cut around an entire border or cut-out area by manual manipulation of a mat knife, particularly when making circular or other non-linear cuts.
It is a principal of the present invention to provide a cutting guide adaptable to permit either linear or circular cuts with a beveled edge in paperboard, or similar materials, with a conventional mat knife.
Another important object is to provide apparatus for holding and guiding a standard mat knife to make either circular or linear cuts in paperboard with a controlled and uniform bevel on the cut edges.
Still another object is to provide a cutting implement holder and guide which permits circular beveled edges to be cut in paperboard matting or framing materials with a standard mat knife with selective control of the position of the blade relative to the direction of cutting to effectively eliminate blade drag due to misalignment of the blade with the cutting direction.
Other objects will in part be obvious and will in part appear hereinafter.